Apparatus for converting heat into work.



APPLICATION FILED AYR.B.1.\1Q.

Patented Mar. 16, 1915.

,4 TTORNE Y5 R. A. FESSENDEN, APPARATUS HR coxvmrm HEAT mm WORK.

APPLIUAIION FILED MR? \ALI.

Patented Mar. 1b, 1915 R. A. PESSENDEN. APPARATUS FOR CONVERTING HEAT 1M0 WORK. APPUUAI'ION FXLED APRAI. 1M2.

1,132,465, Patented Mar. 16, 1915.

5 SHEETS SHEET 4.

'R. A. FESSBNDBN. APPARATUS FOR CONVERTING HEAT INTO WORK.

APPLICATION FILED APB.8, 1912.

5 SHEETS SHEET 5.

Fi 2-5- v I 4/ J4 WITNESSES: INVENTOI? g I BY 4 7 MFJ M ATTORNEYS Patented Mar. 16, 1915.

UNITED STATES PP LITENT OFFICE.

REGINALD A. FESSENDEN, OF BROOKLINE, MASSACHUSETTS.

APPARATUS FOB. CONVERTING HEAT INT O WORK.

Application filed April 8, 1812.

To all whom it may oncern:

Be it known that I, REGINALD A. Fnssniz- DEN, a citizen of the United States, and a resident of Brookline, in the county of Norfolk and State of Massachusetts, have'invented certain new and useful Improvements in Apparatus for Converting Heat into \Vork, of which the following is a specification. i

While my invention obviously .is capable of adaptation to various types of therrnic motors, I shall describe the same in connection with an internal combustion engine.

The accompanying drawings illustrate an internal combustion engine comprising in its construction one embodiment of my in vention.

In the drawings-Figure 1 is a view of what 1 term an engine element, the portion of said figure on the right of the irregular line X being shown in longitudinal section and the portion on the left of said line appearing in elevation. in this figure the pistons are shown in the position which they occupy at the end of the explosion stroke. Fig. 2 is a similar view of said engine element showing the pistons in the po sitionoccupied at the end of the compression stroke. Fig. 3 is a view of an internal combustion engine having the two engine elements shown in Figs. 1 and 2 arranged end to end, that portion of the figure to the right of the irregular line Y being shown in section and the portion on the left of said line being shown in elevation. In this fig are the side plates 255 are omitted for clearncss. l igs. -"l and 5 are trans erse sections when on the lit... *l- 'l and 55, respec tively. of Fig. 3. Fig. (3 is a side elevation of the engine shown in Fig. 3 as it appears from a point ninety degrees away from the view point of Fig.3, with the side plates 33 in position. Fig. 7 is a transverse section taken onthe line 7-7 of Fig. 3. Fig. 8 is a fragmentary longitudinal scctionon an enlarged scale showing a modification of the linder construction.

In the particular drawings selected for more fully disclosing the principle of mv invention. 1 1' are cylii'iders provided ith the circular hinges or cylinder supports it ll respectively. each flange being shown in the present instance as cast integral with its cylinder. The pistons 3 3' cooperate Specification of Letters Patent.

Patented Mar. 1 ,1915.

Serial No. 689,179.

with the cylinder 1 and the pistons 3 3" with the cylinder 1. Each piston is in noncontact fit with the inside of the cylinder and in contact lit with the outside there of,in other words, the sliding surface of contact between the piston and cylinder, or the piston-bearing surface, is on the outside of the cylinder. In the present case this is effected by providing each cylindrical cupshaped piston body 3 3' 3" having an external diameter slightly smaller than the internal diameter of the cylinder with an inclosing cylindrical bearing-member or sleeve 2 i" 2 2, the internal diameter of uhich is equal to the external diameter of the cylinder. This is the salient feature of my invention. lily means of it I am enahled to overcome a number of difficulties heretofore experienced in this art and to accomplish various new and useful results as hereinafter more fully set forth.

in the engine of the prior art, Where the sliding surface of contact between the piston and cylinder, or the piston-bearing surface, on the inside of the cylinder, pis ton-packing rings, which for various reasons are objectionable, are necessary, as is well known, to compensate for-the expansion of the cylinder and the contraction of the piston caused by the pressure exerted on these elements by the working fluid. But, by means of my external piston-bearing, the

use of suchrings' rendered unnecessary,-

i'or the pressure created inside the cylinder causes both the cylinder 1 and the piston hearing member 2 to expand in the same direction and tighten the ontact there-between, the friction between these two elements varying directly withthe pressure in the cylinder, so that for very large expansions. ei'en expansions to or below atmospheric pressure, there are only very small frictional losses, the pressure between the piston-hearing memher and the cylinder, and therefore the friction therebetween, heing lessened as the pressure of the working lluid is reduced. In short, the engine is sclltigliteiii1ig and automatically-compen sating for cylinder expansion to prevent leakage. not needed. By referring to Fig. 2 for in her explanation with reference to a can it et. example, it will be noted that when, as therein shown, the pistons are at the end For this reason piston rings are.

of the compression stroke, and the working fluid is in its state of maximum compression, the leakage surface is largest; but at this instant the pressure and friction be tween the cylinder and the piston-bearing sleeve is also a maximum, for the area of the cylinder exposed to the action of the working fluid is now much greater than that of the piston-bearing sleeve so exposed, the latter surface being equal merely to the combined areas of the ports 5 (or 5") so that the cylinder expands at a greater rate than the piston-bearing sleeve, and such expansion tightens the. contact between the cylinder and sleeve instead of pressing these elements apart. By virtue of this construction, very high pressures, for example one thousand pounds per square inch, are possible and practicable on'compression, although in general such high pressures are not necessary.

As the engine is of the long-stroke type, the exhaust gases are much cooler than in the internal combustion engine heretofore employed, and a very long stroke may be used, because as above explained, the fric- 'tion between the inside of the piston-bearing sleeve 2 and the outside of the cylinder 1 varies directly with the pressure of the working fluid.

I shall now proceed with the detail description of the illustrative embodiment of my invention shown in the drawings.

The cylinders 1 1' are provided neartheir ends with a plurality of ports 5 5 and 5" "5" respectively, herein shown as eight in number, although of course any other suitshown in Figs.

able number may be employed, and the ends of the piston-bearing sleeves 2 2" are pro vided respectively with the supplemental exhaust ports 7 7, (Figs. 1, 2 and 3,) of much smaller area than their-cooperating ports 5 5. The external surface of the cylinders 1 1 on which the piston-bearing sleeves rub in their travel, are provided with lubricatingoil grooves 9 9' respectively, the construction being'such that as is obvious, the hot products of combustion cannot come into contactwith said grooves or the lubricant which by any suitable means may be supplied thereto, and each cylinder is provided with a fuel inlet tube or duct K K, such ducts being shown in the present instance as bored transversely through the flanges R It (Figs. 1, 2, 3 and 4:.)

A pair of engine elements such as shown in Figs. 1 and 2 preferably are employed suitably mounted for cooperation, and as 3 and (3, they may be mounted end to end in the following manner: To the flanges or cylinder-supports R R are secured as by the screws 7" r or otherwise two oppositelydisposed parallel steel sheets 35, (see Figs. 4. 5, 6 and 7) so that the cylinders 1 1 remain in fixed position and shown as four in number, which are screwed into or otherwise attached to the lugs 13 13, preferably formed integral with the outer ends of the piston-bearing sleeves 2 2', respectively, and screwed into or otherwise attached to said support 30, said rods freely passing through the holes 15 in the flanges R R. (Figs. 3, at, 5 and 7.) Connecting rods 32 are pivotally attached to the support 30 by the pins 30', the inner ends of which extend beyond the ends'of the pin 31, so that the latter will clear said support, and are connected to the cranks 34 34' se cured to the crank-shaft 34 at an angle of one hundred and eighty degrees from the cranks 3i". i

The length of the stroke being governed by the throw of the cranks, the pins 30 at the end of a half revolution of the crankshaft from the position shown in Figs. 3 and 6 will be'as far below the pin 31 as in said figures they are shown above the same.

It will be noted that one pairof rods 32 is always moving up under tension when the other pair 33 is moving downunder compression, and that such tension and compression are necessarily equal, as they are due to the same explosion in the same cylinder. Consequently there is no unbalanced up or down pressure on the bearing of 3 K, and this bearing could be elim ated if. it were not necessary or rather cesirable to fix the position of the shaft 31 relatively to the engine, in some way, and where this is not necessary, or is done in another way, the bearing may be omitted. There is a side thrust which may be eliminated by suitable construction, .but this is not neces sary as it is very slight, owing to the fact that the rods 32, 33 are more than ten times longer than the crank throw, and the cranks are at right angles to the axis of the piston when the expansion is half over andthe con'iprcssion much fallen. For this reason and because at this instant each piston element pair is equally supported by its cylinder pair. and because will; an ordinary 30-50 ll. 1. engine, the sidq; thrust only amounts to less than ten pounds per square inch, no piston or other guidiis are necessary. the cylinders them selu s taking up the side thrusts and being well lul; ricatcd. .(ln ac ount of the perfect balancing and tllCqPCll ifi' scavenging hereiii) inaftar mrim engine mm mm at wry high ll akimg the standard fig urea far velocity lnund practical for scavan in {was the limiting! velocilv is in the neighlwrlwod of tweil v9 filwuszmd revcilu $10111; per minute, a very high speed and one which would not be used in practice as a rule.

It will nnw be, that the side-plates 35 may be thin metal sheets, as there is no fume tending to displace the cylinder elements limgiturlinall g. except the friation exerted film/r2021 by the pistcin-briarizzg SlE E Q. Em mick pismn acts equally and uppositaly 11;:013 wasting pisrmr The angina is Elms iii-lily land. not men,. .pparemly} balanced for all speeds. This is not true when the appoa le meving pistens are in sqmmle explnsiun cinunbers as in his latmr case, if one fails t0 explode, the full unbalancing forces came into play,

It will be zmlzfli that rile reds 15 which aonmect the mill??? pismns the encircling suppert 36 are always under tensiol'i and that therefmfe flu: ma lw (if reialiwlr small oliameter Casings ur'mntainers 4 4: herein shown as cylimlrical, suitably aitached to the flanges H ll respgcsivrly and iii-close the upper half 0f the cylindsr 1 and tire lower half of the cylinder 1, loge-Cher with the pismns 3 3 Wliiull miip'sram with said cylinders. Thaw csntainers: or mmpression cases may of suitable matfirinl and. may haw any desired shape and each will b6 provi ied .with an automatic air inlet valve (not shown) as. is usual in an oz'rlirmry two-cycle engine, s00 fur axai'n ilc, lie patent t0 Hurrl T189 53, dated Jammy 20, 1903 aml the pa l1 ent t0 Ntiwcumb LQOEUQE. dated November 1911, in lllll l EGHIPIQHSlOZ] mars liming ills, fmlclinn of Sill-'l conta ners a are illuslirutm'l and iii iii-Jill in LlPilil. Spark-plugs 8 13 if 2 m; I v in: screwed into the minimal: m the cup-shaped pistons 3 3, so xlmt their Sli f'lll puma will pwlecr into {lift imrl' film n! liillnlnl'fi. l l. l",

.llmh mil 1' .lflrmrzs pr m,

i if; arr? Qm'plOyQLl in l1l=vranally inauizitu the: interior of the ((fihlHlSliOl'l i'lmmlmr from the cylinders uml pistnns. in ti)? prawn: Kiw -liner l mupln 'l'm ti 7 pub pose 11h steel line l0 U3 fur the :zvlinl'lurs l l r rpwtlrelv ll 1 far the pistnnrs 515 3 fl" 3. Rush liner being s liyigimll in or over the cylinder and pis ma null mica i-arr r Ill llI" for the rfilinnlei. 1nd mfor the pistnzie, ill: mica slaps l gala-10ml l-Qt'fflfill the llnrara. mill tlm may lie, T 1

detail in Figs. 1. 2, 4., and 8.1mm, in Fig. which drawn to ane half the scale of 1 and 52., in orcler to simplify the drawing, the liners are nut shown and the refemnw disaracters M M m m m" m may be considered to re resent tlw heat-insulating means shown in retail in the other figures.

It will be llXlLlCIStOOdL of sourae that; in stead of mica any other suitable material may be used, as for example asbesisos, 01' asbr-stas and silicate. of soda, 0;" even. plain air space, the. liners being separalad mm the, Walls by washers or projectiisiim and iiiw eaal of the sfiefil liners, liners of mica, 01 a es- $055, 01' silicon m carburundum m @lnr able material may he amplm aei'l or poi-"lain or similar material with pr wiihout Wires; nr wire netting HILlJOK'lUlQd in it. raposml surface of the liners may be provided. with Li coating B (see. Fig. cf any suitable mzv terial siisli as mica. asbestos fused stance, or Bwzerilarz'lefl (U2Zl3k'."- 024ml 0;. or they may be tinned 11 nicllteled or bi-liififl" wise Heated.

The ports preferably are hushed Willi. thermal insulaturs 6, which may we 01" the same character as those used to heat-insulate the cylinders and. l$t0fl5 and the lips; L L L" l'j'" iff the p wonliearing sleeves may ails) be Mat-insulated as: shown.

.ln operatimi the interior liners of the conllmstiurs chamber maintain a, high tern peralure, which may be even :1 dull red but as the heat. cannot pass to the cylinder ur platen these rcmain 0001. and the limit is expended in doing work or passes away with the waste guws, which may if desired, be n9] to reheat. the air fur an air motor qr umlier gimrposes.

"hi amount of the gnarl heat insimtion and of the high temperature 01 (hrit not necessary. as will), he Dlmrl an gin: in use high mm'ipml: inns, though filmy are prrferrml. l liez: at prs (if wil lruniirevl pmuuls the fuel ill ignite, 113 in lug: llijvllffi l mm :blir rylirnii and on 0mm lug llfiin cmgtm'it wi 1., in \vl'i l, flirmxgli pa $21510 way ,s: all.

The CfiIlSlI'llCtlOfl abo e described is (tapalile if various uses and YV'lilllml; limiling myself thereto. 1 shall now describe several 1/Os: il)lO modes of operation,

Wlwn rn'iployed an intlgrnal comb tion engine g aseous liquid or solid fuel, ur any combination 0f such fuels may rim plnyaril. as is now well iuulersmcrl ilm art. liy nwans Iii upyzu-ntus nuw will lmmvn and which c m:-slilut(=s 110 part cf my invention, (ail m3 Other 1" may be ill trnslwre rl through the (limits K ii' in such a way 2.1; 110i; to ba imtirely farmed inn; a

mixture with air before introduction, although a mixture of air and gas, or of oil and coal-dust, etc., may he so introduced. Apparatus suitable for this purpose has been described by Diesel, for example in Letters Patent 542,846, July 15, 189;"); 608,8-l5, August 9, 1898, and 890,620, June 16, 1908. Such fuel so injected into the combustion chamber is exploded by contact with the heated air produced by com pression or by contact with the hot liners 10 10 or otherwise in any of the methods described by Diesel and others. Near the end of the explosion stroke, the supplemental exhaust port 7 begins to uncover one of the ports 5 and the pressure in the cylinder it begins to fall. The ports 5, 5 then are uncovered by the piston-bearing sleeves 2 2' and the burned gases exhaust through said ports. However, during the compres sion stroke (Fig. 2) the container is filled with :ii' and this air, at the end of the explosion stroke (Fig. l) is compressed.

'Iherefore just as soon as the sleeve 2 be-- gins to uncover the ports 5, the compressed air in the container or compression chamber 4 enters the cylinder by way of said ports and clears it of the products of combustion which pass out through the ports 5'. At the end of the explosion stroke in cylinder 1. an explosion takes place in cylinder 1, pistcn 3 is forced downwardly and car ries piston 3 with it and piston 3" is forced upwardly and carries piston 3' with it, the said pistons 23 and 3' thus moving toward one another on their compression strokes, while the cylinder 1 is scavenged or cleared of the burned gases by the air compressed in the crntainer 4 in the manner above set forth in connection with the scavenging of cylinder 1.

In lieu of operating the engine as a llicsel engine, a gaseous mixture may be drawn int the ccntaincrs 4 4 on the compression strokes of the pistons 3 3 by way of the automatic inlet valve referred to above as provided for the admission of air to said c ntainers, and compressed in said containers on the explosion stroke of said pistons 3 3". In such case any desired amount of pre-coniprcssion may he obtained and the mixture so CUD'IPIQSSQd will {low into the cylinders by way of the ports 5. thereby displacing the products of coinhusticn which pass out through the ports 5' 5" in the usual well known manner, as descri ed. For (X11lIl]')lP.lIl the patent to Ncwcomb al'oresaid. This plot-(impressed inixture is of course further c m 'ircssed until the end of tho wnnoro sion stroke whrn, by means f spark-plug or by the heat of compression. or ith rwiw. it is ignited and (X'- plodes. causing" the pistons between which it was ('(Illl7l(" -l"l,l to malo-.thcir cvplosion stroke, at the end of which a new charge is '0 5", the ducts ii K. are not necessarily w received and the cylinder scavenged as before. It will be understood of course that where a mixture is pre-compressed in the containers and introduced by way of ports" employed for fuel induction, although they may be so employed for injecting rich mixture in cases where a lean mixture is admitted by way of ports 5 5'. it will also be understood that when the engine operated as a Diesel engine, instead of ad mitting pure air by way of the ports 5"" and in ecting fuel by way of the ducts K K, a lean mixture may he admitted by way of said ports and a rich l'lllKtllZQ injected,

The idle space in the cylinders, between the sleeve 3 and the piston body 3, is pref erably so proportioned that on cijin'ipression the pressure of the gases or air filling the idle space is the some approximately is that in the main c linder. In this case i but little exchange of ir or gas l the idle space and evlmdcr. especially the injected fuel n'icth d oi. operatini, practically no u of energy. the en of compression of the "uses or air in the idle space being given ha on expansion. l this construction mca is atl'orded for preventing the combustion from occurring ll contact with the sliding surface between the piston and cylinder, or the surface of the cylinder on which the piston rut-s in travel.

It will he seen that the engine is of the two-cycle type, because, as above described, the ports open at one end of the stroke, allowing the burnt gases to ilow out and admitting the air or mixture, and then compressing the air or mixture during the first half of the stroke, exploding the mixture or injected fuel. and expanding during the sec ond hall' of the stroke hen exhaust again. occurs: although it may be used as a foil/-- cycle engine. and oh ionr'ly my iinprm cl construction embodying said hearing pm tons and thermally insulated parts may be used in the steam engine, he air compressor or the air motor.

it will he noted that there are two iiiopulses or explosions per revolution, because there are two twoc cclc cylinders, and in a twoc vcle engine there is; one explosion per revolution, so that two twoc cle cylii'zde s in oppo ite phase, as in the present ('11P produce two explo ions per revolution. The 128 engine thcrel'orc is .louhlc-actime and equivalent to the (our cylinders of a fouo cvcle engine and much simpler and m re eflicicnt.

lcrctolore in heat cngincs the ellicieocy of the engine has been limited by the fact hit the i-llluivnci' primarily depends upon r' rangioi t mperature of the work; uid. and i zir, range has liccn liinird he beat hoses due to conduction, evaporal l t ianne tion, condensation, etc, in the cylinder and its neighborhood, and also by the fact that with high temperatures the piston moved over, and in contact with, the walls of the cylinder or combustion chamber, thereby limiting the temperatures to those at which lubrication was possible, wheresolid pistons were used, andto those at which the evaporation and cooling were not too ex cessive, where liquid pistons were used.

By my invention great economy in the use of fuel is attained. The thermal eiliciency of heat engines is measured by the difl'erence between the upper and lower limits of the temperature of the working fluid, divided by the absolute temperature of the upper limit. Obviously therefore the lower the temperature of the issuing working fluid, the higher the efliciency. In the ordinary internal combustion engine, the issuing gas is very hot, i. 8., the lower limit is hiuh,and the efliciency low. In the steam eng ne it cannot go below the temperature of freezing water. But in my engine, for thereasons hereinhefore stated, the expansion can be carried out to very low pressures and temperatures, so that the issuing working fluid may be many degrees below zero. Since the .ens ine exhausts into the air, there would be back pressure unless the air was at the same temperature as the issuing fluid, and for this reason the whole engine may be placed in a chill room at any desired low temperature. E en without this, in large sizes of 1,000 H. P. and upward, the thermal efliciency may reach over 80% and the brake eiiiciency over 70%;

By means of my invention I am enabled to overcome the difliculty heretofore experienced of maintaining the piston packing rings tight and cool, and the preferred form of my engine balanced for all soeeds,

needs no cooling by water or air-flanges {though such cooling may be used if desired,

and in very large sizes is preferable) has no valves, springs, Water pumps, fans, magneto,

snark-plugs, timers, gears, shift-levers,

clutch, bedplate, carburetor, etc., though any or all of these may be used.

By the term piston as used herein is meant that element of an engine which moves back and forth inside the cylinder and thereby changes the amount of working fluid in said cylinder.

Having thus described in detail one illustrative embodiment of my invention with out, however, limiting the thereto, what I claim as new and desire to secure by Letters Patent is- 1. A thermic motor comprising in comhi nation a. cylinder, a piston-body having its external diameter smaller than the internal diameter of said cylinder, and a sleeve secured to said piston-body and having its in- 65 ternal diameter equal to the external die me having its ter of said cylinder. said sleer ,J t Z said cylnr 6.- bearing surface on the outside of der.

'2. A tllfilnllij mot. comprising in cumhi. nation a cylinder and a piston, said piston being in uon con 'jaci-iii with the llltLIIOl oi".

said cylinder and in conta t with the tcrior thereof, said piston l iug bearing surface on the outside of said cylinder.

3. A thermic n'mtor comprising in cumin nation a cylinder, cup-shaped piston haw ing its external diameter smaller than the internal diameter of said cylinder, and a sleeve secured to said piston and having its internal diameter equal to the external diameter of said cylinder, said sleeve being so extensive with said piston, and having its bearing surface on the outside of said cylinder.

4. A thermio motor comprising in combination a cylinder ,and a piston, said piston being in non-contact iitwith the interior of said cylinder and. in contact fit with the terior thereof, said piston having its hearing surface on the outside of said cylinder, and a lining of heatinsulziting material for said cylinder.

5. A thermic motor comprising in coiiihination a cylinder and a piston, said piston being in DOIPCOHKQCQ fit with the interior of said cylinder and in contact it with the teri or thereof. said piston having: its bearing surface on the outside of said cylinder and a lining of heat-insulating material for said piston.

6. A thermic motor comprising in combination a cylinder and a piston, m d cylinder being proiided with ports, and said piston being in non-contact fit with the interior of said cylinder and in contact fit with the ex terior thereof, said ton having its bearing surface on the outside of said cylinder, and a heat insulating lining; for each of said ports. I

. A theriuic mote:- comprising in comhi. nation a cylinder and piston, said pie i be {5 in non-contact lit with the interior is said cylinder and in contact fit with the essurface on the outside of said whereby. the hot products of winihustiun ar WMM-iws grees' apart, means connecting the two outer pistons to one crank and other means connecting the two inner pistons to the other crank.

9. A thermic motor comprising in combination a cylinder, a piston-body having its external diameter smaller than the internal diameter of said cylinder, a sleeve secured to said piston-body and having its internal diameter equal to the external diameter of said cylinder, said sleeve having its bearing surface on the outside of said cylinder, and means for thermally insulating said cylinder and piston-body.

10. A therrnic motor comprisin in combination a cylinder, a piston-b0 y having its external diameter smaller than the internal diameter of said cylinder, and a sleeve secured to said piston-body, said sleeve having its bearing surface on the outside of said cylinder.

11. A thermicmotor'comprising in combination a cylinder, a piston-body having its external diameter smaller than the internal diameter of said cylinder, a sleeve secured to said piston-body, said sleeve having its hearing surface on the outside of said cylinder, and means for thermally insulating said cylinder and piston-body.

In testimony whereof, I have hereunto subscribed my name this 6th day of April REGINALD A. FESSENDEN. Witnesses:

E. B. TOMLINSQN, G120. K. WOODWORTH. 

